Protein kinases play important roles in cellular signal pathways that regulate various cell functions such as differentiation, proliferation, migration, and apoptosis. Deregulation of protein kinases is implicated in a number of diseases including cancer. Thus protein kinases are attractive therapeutic targets in cancer treatment.
Aurora kinases, belonging to the serine/threonine subclass of kinases, are involved in the regulation of mitosis. Three isoforms A, B and C are known. Aurora A is involved in centrosome maturation and separation, bi-polar spindle assembly and mitotic entry; Aurora B and C are essential for accurate chromosome segregation and cytokinesis. The deregulated Aurora kinase activity has been linked to genetic instability, defects in centrosome function, spindle assembly, chromosome alignment, and cytokinesis, all of which can lead to tumorigenesis. For example, both Aurora A and B levels are up-regulated in various cancers, including breast and colorectal cancers. Thus, it is of great interest to develop Aurora kinase inhibitors as anti-cancer drugs.